@SFS the new posts/activity area is a little weird because there are two different views, New Posts and
Recent Activity. Next time you're in there check the urls: one is /whats-new/ and the other is /whats-new/posts/. It could be that one works better for you than the other.
Anyway, glad it's working in this 5 minute period!
@Phil Herring - Forgot to do the above when I checked new posts today, but observed the following, which is different (a hybrid?) behavior from what I have described previously, in case it helps you in some way.
1) On the left side of the page, I clicked on the arrow beside "Forums" to trigger the popup menu.
2) I selected "New Posts" - what was returned ran to 15 pages of threads, which is odd, as I looked at posts yesterday afternoon. I resigned myself to lots of mouse clicks.
3) Beginning on page 1 of 15, for the threads I was uninterested in, I selected "Mark as Read". (BTW, I really like the confirmation I get at the top of the screen every time I use this button.)
4) At the end of page 1, down at the bottom, I select "2" to go to the next page, and at the top I start using "Mark as Read".
5) About halfway down page 2, the threads no longer have a "Mark as Read" option, and the posts that cannot be so marked are from around the time yesterday that I last checked for new posts. "Cool", I think to myself, "that's new to me, but clearly makes sense."
6) So I go back to the left side of the page, trigger the same popup menu under "Forums", and ask for "New Posts". It returns a list of just 4 threads, the ones I was interested in reading, and for which I had purposefully NOT used "Mark as Read".
Although I don't know why it started with a list of 15 pages of threads it thought contained "New Posts", I was glad to see that the net result is that it worked the same as the old system.